@misc{indiciae4de27cf8031a,
  title = {40Ar/39Ar age-spectrum data for whole rock samples of the Martinsburg Formation, Lehigh Gap area, Pennsylvania},
  author = {Michael J. Kunk and R. P. Wintsch},
  year = {1996},
  doi = {10.3133/ofr9695},
  url = {https://pubs.usgs.gov/publication/ofr9695},
  note = {Source identifier: ofr9695}
}